To assure the uncontaminated delivery of contained products to a consumer, and particularly medicinal products that are taken internally, there is a need for a container that includes an indicator that indicates to a consumer that the contents of the container have not been tampered with from their point of manufacture to the point of consumer sale.
A fundamental prior art approach toward meeting this need is seen in the so-called "telltale" indication, i.e., a readily discernible characteristic indicative of tampering, such as a signal that some person has previously attempted to gain access to the container contents. Broadly speaking, this approach can be generalized as placing a tamper-indicating member, e.g., a tell-tale, in the path of access to a container to indicate tampering by discernible change.
Prior art telltales may be categorized in respect of the relative location of the telltale to the container access port. For example, some known telltales are located directly at the access port spanning the access opening, e.g., are secured across the mouths of jars. Other known telltales, such as plastic sleeves which are heat shrunk about a capped jar, are located in the path of access to the container but not directly across the access port to the container. Because telltale items located outside a container cap may be removed leaving the remaining capped container without tamper indicating capability, telltales located directly at the access port spanning the access opening offer a higher degree of security than those located externally to the cap.
Of the various known telltale devices located directly at the access opening of a container, those that are closure member activated generally offer a higher degree of security than those that are not closure member activated. In the closure member activated category, reverse sensing (opening) movement of the closure member, e.g., cap, brings some element into tearing relation with the telltale.
U.S. Pat. Nos. 4,793,122 and 4,793,505 to Towns et al. (hereinafter "the Towns et al. patents") describe various arrangements for closure member activated tamper-indicating closure devices. However, the disclosed closure devices suffer from various manufacturing and use disadvantages which will be discussed with reference to FIGS. 1-5.
Referring now to FIG. 1 there is illustrated a representative embodiment of the known tamper-indicating closure devices described in the Towns et al. patents. As illustrated in FIG. 1, the known closure device comprises a hollow cap 10 including tines 12 for puncturing a tamper indicating element. As illustrated, the tines 12 are radially offset from the center of the rotative movements of the cap 10 and extend parallel to the axis of the hollow cylindrical cap 10. Thus, the primary extent of each tine 12 extends generally radially of the cap's center of rotation to provide a frontal expanse for rupturing or tearing of the indicating element when the cap 10 is rotated.
Referring now to FIG. 2, it can be seen that when assembled, by insertion of the indicating element 16 into the cap 10, the tines 12 pierce the indicating element 16. Referring now briefly to FIG. 5A, which is a top view of the cap assembly of FIG. 2, it can be seen that because the tines 12 pierce the indicating element 16, the color layer beneath the top layer of the indicator element 16 can be seen through the top of the cap 10, as indicated by the shaded areas representing the position of the tines 12.
While tamper indication is important, it is also desirable to provide an air tight seal on a container to protect the contents of the container from atmospheric deterioration in many instances. Because the tines described in the Towns et al. patents pierce the indicating element, when an additional seal is not used, it is necessary to use a sealant coating for purposes of resealing the puncture caused by the tine in the indicating element or by applying a sealant to the puncture areas after insertion of the indicating element into the cap in order to achieve an air tight seal.
While an air tight seal may be achieved by securing a seal to the container after filling but before the cap is secured thereto, because the known tines 12 extend beyond the indicating element 16, they are likely to pierce any seal placed over the opening of the container unless certain steps are taken to avoid such puncturing of the seal. The Towns et al. patents describes the flattening of the tines 12 through a staking operation. Such a staking operating results in the cap assembly, illustrated in FIG. 3, wherein the tine ends are forced into a flat-tearing disposition generally parallel to the undersurface of the cap 10. Once such a flattening operation has been performed, the cap 10 can receive an underlayer 18 having an integrity that is unaffected by the operation of the tines 12. Alternatively, the cap 10 may be attached to a container having a seal placed over the mouth of the container without the risk of the tines 12 piercing the seal and exposing the container contents to atmospheric conditions.
While the tamper indicating closure devices described in the Towns et al. patents provide a high degree of tamper indication, there are several features of the closure devices associated with the piercing of the indicator element that remain to be improved upon. For example, as a result of the piercing of the indicator element by the tines, the color portion of the indicating element is exposed through the cap in the areas of the tines. This exposure of the colored areas may cause some confusion with consumers who are unfamiliar with the tamper indicating device and may believe that any display of color is an indication to tampering.
More significantly, however, are the manufacturing drawbacks associated with the use of tines that pierce the tamper indicating element and extend therethrough. As discussed above, the piercing of the indicating element requires the use of sealant or an additional seal to provide an airtight seal. In addition, when an underlayer or additional seal is to be used, the tines 12 must first be staked, i.e., flattened, before the underlayer or seal may be used to insure that the tines 12 will not pierce the underlayer or seal. This staking operation introduces a step into the cap assembly manufacturing process that, if eliminated, could reduce the cost of manufacturing tamper-indicating closure devices.